How popular is Carenna?

Carenna is a rare given name for females. Carenna is an equivalently unique last name too for both adults and children. (2000 U.S. Census)

Which version is better?

with its source form and related girl names. Popular related forms of Carenna (not ranked) rated in the Top 2000 are Karina(#462 a year ago), Carina(#1067), Carin, Karena and Caren. Other forms, like Carita, are uncommon. Usage of these forms of Carenna was common in the year 1996 (adoption of 0.23%) and has become significantly reduced since (adoption 0.04%, ▼80%). (2015 U.S. SSA Records)